Re: Steve ugly-build LZ1AQ using MPS2222 sweeps uploaded to Photos
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> But the expected voltages across a small loop in lo-Z shortcut?
> mode are much lower than at fullsize or hi-Z e-field antennas.
> But in principle i absolutely agree with your advice to avoid?
> antiparallel diodes. Better use biased diodes or bidirectional?
> ultra low capacitance TVS Diodes.
From Martin's comment that two 82pF "improved the performance on the upper HF bands", I infer that the Wellbrook also has an impedance that rises with frequency. ? /g/loopantennas/message/19758?
What are the RF performances of biased (forward?) diodes and bidirectional ultra low capacitance TVS Diodes in limiter applications? I haven't encountered these diodes being used in commercial equipment's limiters.
A PIN diode limiter HSMP-4820 turns on at 7 dBm and has IP3 = 15 dBm.?
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> However, this is not the case with broadband untuned loops,?
> and they seem to be relatively insensitive to their surroundings.
?
Aren't the untuned loops also inadvertently tuned? Eg. the LZ1AQ loop is parallel resonated by two 100 pF, and the Wellbrook by the two 82 pF caps. Maybe it the amp's low input Z that renders these inadvertently tuned loops insensitive?
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